Fix typo (#1984)

src/main/java/org/mockito/AdditionalAnswers.java

@@ -276,7 +276,7 @@ public static <T> Answer<T> returnsArgAt(int position) {
      * This feature suffers from the same drawback as the spy.
      * The mock will call the delegate if you use regular when().then() stubbing style.
      * Since the real implementation is called this might have some side effects.
-     * Therefore you should to use the doReturn|Throw|Answer|CallRealMethod stubbing style. Example:
+     * Therefore you should use the doReturn|Throw|Answer|CallRealMethod stubbing style. Example:
      *
      * <pre class="code"><code class="java">
      *   List listWithDelegate = mock(List.class, AdditionalAnswers.delegatesTo(awesomeList));